package org.example.courseservice.service;

import lombok.RequiredArgsConstructor;
import org.example.courseservice.entity.Video;
import org.springframework.stereotype.Service;
import org.springframework.web.multipart.MultipartFile;
import java.io.IOException;
import java.nio.file.Files;
import java.nio.file.Path;
import java.nio.file.Paths;
import java.util.UUID;

@Service
@RequiredArgsConstructor
public class VideoProcessingService {
    private static final String UPLOAD_DIR = "uploads/videos";

    public Video uploadVideo(MultipartFile file, Long lessonId) throws IOException {
        // 创建上传目录
        Path uploadPath = Paths.get(UPLOAD_DIR);
        if (!Files.exists(uploadPath)) {
            Files.createDirectories(uploadPath);
        }

        // 生成唯一文件名
        String filename = UUID.randomUUID().toString() + "_" + file.getOriginalFilename();
        Path filePath = uploadPath.resolve(filename);
        
        // 保存文件
        Files.copy(file.getInputStream(), filePath);

        // 创建视频记录
        Video video = new Video();
        video.setOriginalFilename(file.getOriginalFilename());
        video.setStoragePath(filePath.toString());
        video.setStatus(Video.ProcessingStatus.PENDING);

        // TODO: 异步处理视频转码
        processVideoAsync(video);

        return video;
    }

    private void processVideoAsync(Video video) {
        // TODO: 实现异步视频处理逻辑
        // 1. 更新状态为 PROCESSING
        // 2. 进行视频转码
        // 3. 生成不同质量的版本
        // 4. 更新状态为 COMPLETED
    }
}